Pollutant Concentrations

Air quality readings will be available hourly from 7am to 11pm. Air quality readings from 12am to 6am will be made available at 7am on the same day.

Readings on 16 Jan 2015

View reading for:

Region

24-hr Sulphur dioxide(µg/m3)

24-hr PM10(µg/m3)

1-hr Nitrogen dioxide(µg/m3)a

8-hr Ozone(µg/m3)

8-hr Carbon monoxide(mg/m3)

24-hr PM2.5(µg/m3)

North

8(5)

26(26)

15(-)

37(16)

0.5(5)

13(52)

South

7(4)

26(26)

7(-)

35(15)

0.5(5)

11(45)

East

8(5)

26(26)

12(-)

63(27)

0.5(5)

16(55)

West

2(1)

26(26)

9(-)

58(25)

0.4(4)

12(49)

Central

6(4)

23(23)

28(-)

47(20)

0.3(3)

10(42)

1-hr PM2.5 (µg/m3)b Readings on 16 Jan 2015

View reading for:

Time

1am

2am

3am

4am

5am

6am

7am

8am

9am

10am

11am

12pm

North

16

11

12

19

18

18

17

16

12

16

16

12

South

2

3

4

10

7

11

11

16

14

14

22

20

East

12

18

18

18

23

20

22

16

11

21

24

13

West

6

11

11

9

12

10

8

15

14

18

21

21

Central

2

8

8

8

11

16

11

14

11

9

14

10

Time

1pm

2pm

3pm

4pm

5pm

6pm

7pm

8pm

9pm

10pm

11pm

12am

North

10

13

8

10

9

12

8

11

15

11

13

-

South

14

14

12

13

11

19

7

9

8

10

8

-

East

16

9

9

9

12

13

19

16

17

13

16

-

West

13

13

13

11

8

7

13

6

14

10

11

-

Central

12

8

8

9

10

16

8

16

13

12

5

-

Note:a Sub-index for nitrogen dioxide is reported only when the 1-hr concentration equals or exceeds 1130 µg/m3.

b There is no sub-index for 1-hr PM2.5.

3-hr PSI Readings from 1am to 12am on
16 Jan 2015

Time

1am

2am

3am

4am

5am

6am

7am

8am

9am

10am

11am

12pm

3-hr PSI

36

37

40

47

51

53

54

54

53

54

55

56

Time

1pm

2pm

3pm

4pm

5pm

6pm

7pm

8pm

9pm

10pm

11pm

12am

3-hr PSI

55

52

48

44

42

47

48

50

50

51

49

-

Hourly updates of 3-hr PSI readings are provided from 7am to 11pm. The 3-hr PSI readings from 12am to 6am will be made available at 7am on the same day. The 3-hr PSI readings are calculated based on PM2.5 concentrations only.